Item Charge Assignment Issue......

I tried to assign a Item Charge (Customs Duty - Rs. 1,203,560/-) to some Receipt Lines (a large GRN with 80 Lines). When I try to Assign Charges with “Amount” option nothing is happening and when I suggest “Equally”, it is sharing the cost and assigning. Why it is not working with “Amount” option ?

Both QTY and Amount (Cost) fields must be filled in for Items.

However, EQUALLY works even when only QTY is filled in, as this method distributes ItemCharge evenly between LINES and doesn’t bother about Qty or Amount.